Flood and water damage occurs in homes and businesses due to failed water lines, clogged drains and failed appliances. Water damage can also occur from rising water levels that occur from unexpected rains and flash flooding. Most common damage occurs when the water or flooding happens unsupervised, i.e. when no person is available to take quick action to stop the source of the flooding. Water damage occurs worldwide and is one of the most costly repairs to the owner.
Water damage could be significantly reduced by deploying sensors that could survey unmonitored areas that may be prone to flood or water accumulation, or general areas (such as kitchens, restrooms, and laundry rooms) that have pressurized water lines and appliances. These sensors could be linked to security monitoring centers, local warning signs, or transmitted directly to central security monitoring agency.
Known sensors and detectors solutions involve the placement of a resistive, capacitive, or contact element on the floor to measure the presence of water by detecting changes in electrical current as the water covers the sensor. While these approaches are viable and have been implemented in the field, limitations exist. If the flooding water does not come into contact with the detector, or the detector is not sufficiently covered by water, of at least 1/16th inch depth, the floor sensor will fail to detect the water or flood condition. Also if the water flows around the sensor it also will fail to detect flooding. Use of a water containment barrier may be required to channel the water to the sensor element. Further, contact elements can get contaminated and provide false positives or fail to detect flooding. Finally, the cost of contact sensors remains high.
A number of sensors for timely detecting flood and moisture on the floor of a dwelling or other structure and for eliminating the sources of the flood and minimizing the damage resulting from the flooding are known. For example, U.S. Pat. No. 6,683,535, entitled WATER DETECTION SYSTEM AND METHOD, by G. H. Utke; U.S. Pat. No. 4,266,195, entitled WATER DETECTOR, by U. F. Keefner; and US Patent Application No. 20070001864, entitled WATER DETECTOR PROBE, by H. Gammon all describe various sensors and probes to detect moisture, typically by the contact or resistance measurement method.
Known sensors and detectors such as these referenced above, including the U.S. Pat. No. 6,683,535, teach detection of water utilizing continuity sensor placed on a surface. The water detection system includes an alarm relay and a water sensor. The water sensor includes a solid state switching and amplifying circuit for detecting low levels of current flow and amplifying the signal to activate the alarm relay. In some cases, the water detection system further includes an alarm panel, including visual and audible alarms activated by the alarm relay. In some cases, the water detection system includes multiple water sensors for providing zone protection. Furthermore, known water detection sensors and devices are having active elements that need to be physically placed or co-located on a lower surface or a floor. This requires complicated and costly installation procedures and wiring that must be run underneath of flooring materials or along the wall. Such detectors are also noticeable and intrusive, and must be located out of the beaten path so that they are not damaged by normal traffic and activities.
Further, some known sensors are utilizing hanging probes or surface electrodes that are in contact with or directly attached to the surface being monitored. The sensor must be carefully located to provide representative measurements of the surface under all environmental conditions and requires that the surface be cut for installation of the sensor as well as the cabling. Changes in the flooring or installation of a new flooring may render such sensors inoperational or require sensors reinstallation.
There is a need to develop an unobtrusive, easy to install, non-contact, and low cost detector which is capable to reliably and remotely detect flooding and moisture on the floor of a building, dwelling, house, or similar structure. Furthermore, there is a need in a water detector that has wide area sensitivity without the need to construct water containment barriers or channeling devices.